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DifferentWaysToAddParentheses.java
42 lines (38 loc) · 1.49 KB
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DifferentWaysToAddParentheses.java
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public class Solution {
public List<Integer> diffWaysToCompute(String input) {
List<Integer> result = new ArrayList<Integer>();
int k = 0;
int curr = 0;
while (k < input.length() && Character.isDigit(input.charAt(k))) {
curr = curr * 10 + (int)input.charAt(k) - (int)'0';
k += 1;
}
if (k == input.length()) {
result.add(curr);
return result;
}
for (int i = 0; i < input.length(); i++) {
if (Character.isDigit(input.charAt(i)) == false) {
List<Integer> left = diffWaysToCompute(input.substring(0, i));
List<Integer> right = diffWaysToCompute(input.substring(i+1, input.length()));
for (int m = 0; m < left.size(); m++) {
for (int n = 0; n < right.size(); n++) {
int op1 = left.get(m);
int op2 = right.get(n);
int r = 0;
char op = input.charAt(i);
if (op == '-') {
r = op1 - op2;
} else if (op == '+') {
r = op1 + op2;
} else {
r = op1 * op2;
}
result.add(r);
}
}
}
}
return result;
}
}